I’m working on a Rails 2 to Rails 3 upgrade (I know, just in time for Rails 4), and I’ve been annoyed by the fact that ActiveRecord kept spewing its log statements out to the terminal and not to the log file. After realizing this was not a commonly encountered problem, I realized the culprit was an old, out-dated plugin in vendor/plugins that was looking for a variable called RAILS_DEFAULT_LOGGER which no longer exists, and was then creating a new Logger that just writes to STDERR. Ditching the plugin solved my problem. Sane people probably remove / update their plugins first. For the rest of us, keep this in mind.